Method and alpha machine for grinding of tuning-tongues



Sept. 19, 1933. A, DIX 1,927,154

METHOD AND A MACHINE FOR GRINDING OF TUNING TONGUES Filed Dec. 24, 1950 I i! Q 4 m s k ED521250)": AZ Ym pm ST TES PATENT OFFICE METHOD AND A MACHINE FOR GRINDING F TUNING-TONGUES Alfred Dix, Gera, Germany Application December 24, 1930, Serial No.

504,441, and in Germany May 13, 1930 1 Claim.

The well known method of grinding of tuningtongues uses a grinder which Was placed across the length of the tuning-tongue to be ground so that this latter was treated in the transverse di- 5 rection. The result of the polishing operation in the transverse direction was that the tuningtongue became fragile. Besides this the manner of grinding is very expensive and requires a waste,

of time in consequence of the great diiference between the tuning-tongues; for each kind of which another grinder is necessary which must be separately put on the machine and which must ever be shaped like the finished tuning-tongue.

The present invention relates to a method and a machine for grinding of tuning-tongues and it is the principal object of the method according to the invention to provide only a single grinder for the execution of the necessary grinding operation for the tuning-tongues 1 A further object of the invention is the provision of the grinding tool in such manner that it passes in the same direction as the grain of the metal, the tuning-tongue getting more elastic and proof against breaking and a better appearance.

Another object of the invention is the provision of a machine with a movable slide in which the metal strip which forms tuning-tongues is fastened, whereby this metal strip during the grinding operation is guided over an opening within the table of the machine between the grinder and support provided as a spring-controlled plunger which moves in a vertical direction.

A still further object of the invention is the provision of a template which is provided upon the slide by means of two holding arms, the support being provided with a guiding pin by means of which the spring-controlled supportpresses the metal strip, which may form the tuning-tongues against the grinder according to the curved portion of the template during the sliding along of the slide provided with the curved template with the result that the metal strip gets ground in exactly the form of the curved template.

These and other objects and advantages of my invention will become more fully apparent as the description thereof proceeds and will then be specifically pointed out in the appended claim.

In the accompanying drawing forming a material part of this disclosure:

Fig. 1 is a view of the machine, fragmentary in section,

Fig. 2 is a vertical section, laterally seen.

Within the constructional embodiment the slide a of the grinding machine receives the metal strip to be treated which is held by means of the smoother device I) and pushed over the opening within the table of the grinding machine between grinder d and the lower surface of the support 6. This support is movable in vertical direction and is always pressed against the strip 0 by the compression spring f. Upon the slide a holding arms 9' are arranged for receiving the template h, which is arranged in a suitable manner so that it may be easily removed, the guiding pin 1' fixed upon the support c runs on the curved template while the slide is operating. By means of this guiding pin the spring-controlled support c with the metal strip 0 are forcedtowards the grinder d so that the metal strip 0 gets exactly the same form like the curved template h.

A diamond is is arranged and held movable in a parallel direction to the axis of the grinder for the purpose of maintaining the grinder always in a cylindrical form.

By the foregoing manner, the result obtained is that all kinds and shapes of tuning-tongues may be ground. By the large operating surface of the grinder and by the fact that the grinding operationtakes place over the whole breadth of a metal strip a very satisfactory result is guaranteed. It is to be understood that a particular advantage is obained by the fact that the grinding of the tuning-tongues is effected in the same direction as the grain passes, whereby an extraordinary elasticity and considerable security against breaking is given.

It will be clear that changes may be made in the general arrangement and in the construction of the minor details of my invention such as fall within the scope of the invention without departing from the spirit thereof.

Having thus described my inventionwhat I claim as new and desire to secure by Letters Patent is:-

In a grinding machine, principally for grinding tuning tongues, a movable slide support for the strip of material to be ground having an opening through which the grinding tool engages the material, a spring controlled plunger holding the strip of material against the grindena holder frame on said slide support, a template on said holder frame, and a pin on said plunger adapted to glide along said template to impart to the material strip the form of the template, a smoother for the ground strip in front of said holder frame, and a means for .keeping the grinder in proper shape.

ALFRED DIX. 1 

